Resistance training for developing strength, agility, and/or accuracy in a stick sport, such as baseball, golf, or lacrosse, is accomplished using a variety of means, include methods involving elastic resistance bands attached to a training stick. Some solutions employ a simulated stick attached to an elaborate machine, such as in a golf swing training device, or employ a modified stick attached to a resistance band, such as a rod emulating a baseball bat. Unfortunately, these simulated methods don't allow the player to use his or her personal stick, or they limit the training location to wherever the machine is mounted. A simulator may not allow the player to develop accurate proprioceptive awareness of where his or her body is in space.
Other solutions attach weight, or a resistance band, to the shaft of a stick via a clamp, hole, Velcro®, or a U-bracket, thereby allowing the player to utilize a personal stick. Unfortunately, these methods may provide uneven resistance if the attachment mechanism, such as a clamp, cannot swivel freely during shaft rotation, lateral movement, or angular deviation of the stick, and may thereby transmit unnatural dynamics to the player. Alternatively, attaching a universal joint to a sport stick and to an elastic band may provide more realistic resistance dynamics. Regrettably, existing universal joints are designed to restrain a shaft which is linked to a motor or a machine, and are not designed for a universal range of motion over several feet of distance. Furthermore, prior art bearings are made of steel and optimized for high speed rotation. Additionally, the wearing components of the bearings must be co-formed in an expensive process; field repair or field assembly is generally not an option.